Hoisting-derrick.



PATENTED JAN. 22, 1907'.-

J. BASS. HOIS'TING DERRICK. APPLICATION FILED NOV. 15. 1906.

WITNESSES v Aftorre);

In: NORRIS PETERS co., WASHINGTON, D. c.

UNITED STATES PATENT @FFTQE.

JOHN BASS, OF MOKEES ROCKS, PENNSYLVANIA.

HOISTI NG-DER-RICK.

Specification of Letters Patent.

Patented Jan. 22, 1907.

Application filed November 15, 1906. Serial No. 343.504.

To all whom it may concern.-

Be it known that I, JOHN BAss, a citizen of the United States of America, residing at McKees Rocks, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Hoisting-Derricks, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to hoisting-derricks,

and its primary object is to provide improved means for strengthening and reinforcing the mast-support of the derrick.

A further object of the invention is to pro vide improved means for pivotally supporting the mast and for connecting the boom upon the mast.

The construction of the improvement will be fully described hereinafter in connection with the accompanying drawings, which form a part of this specification, and its novel features will be defined in the appended claims.

In the drawings, Figure l is a side elevation of a hoisting-derrick embodying the invention, the mast and boom being broken away for convenience of illustration. Fig. 2 is a view in perspective of the cone-bearing for the mast. Fig. 3 is a similar view of the brace or holddown for holding the mast down to the cone, and Fig. 4 is a similar view of the socket-block for supporting the lower end of the boom.

The reference-numeral 1 designates a base, upon which is firmly bolted a bearing comprising a circular plate 2, formed with boltioles 3, and a conical standard 4, surmounted by a mushroom-head 5.

The numeral 6 designates the mast, the lower end of which is seated in a socket 7 formed in a casting 8, said casting being formed 011 its under face with a semispherical recess 9 to receive the mushroom-head 5.

Projecting from one side of the mast near its base is a boom-seat having parallelbrackets 10, between which is pivotally secured a socket-block 11, which receives the lower end of the boom 12, the block being secured to the boom with a butt-joint and by bolts 13. Tie-plates 14 are bolted to opposite sides of the boom and socket-block 11, securing said socket-block to the boom, avoiding friction.

In the operation of derricks of this class heavy strain upon the boom when the latter is at an angle of about ten or fifteen degrees, more or less, to the mast is likely to cause the mast to kick off the cone or base, and for the purpose of holding down the mast at that point and avoiding the liability of the mast kicking off its cone and breaking the stiff guys or gudgeon-pins I provide a brace or foot-plate 15, firmly bolted to one side of the socket-casting 7 below the brackets 10," and having a horizontal inwardlyprojecting flange 16, rounded on its inner edge 17 to adapt it to fit around the conical standard 4 and engage below the mushroom-head 5. This reinforcement of the mast at its pivotal point causes a part of the lateral strain upon the mast to be transferred or diverted to the point of engagement of the flange with the head 5 of the mast-bearing, thus relieving the mast to that extent.

The derrick is equipped with ulley-blocks 18 and a cable 19 and a suitab e connection 20 between the upper end of the mast and the upper end of the boom; but as these features constitute no part of the present invention a specific description thereof is not necessary.

What I claim, and desire to secure by Letters Patent, is

1. In a hoisting-derrick, the combination with a base, of a bearing consisting of a plate secured to the base, a conical standard rojecting from said plate, and surmounted y a mushroom-head, a socket-casting fitting said head, a mast supported by said casting, a boom pivotally secured to said mast, and a brace secured to said casting and provided with a flange to engage below said head.

2. In a hoisting-derrick, the combination with a base, of a bearing consisting of a plate secured to said base, a conical standard rojecting from said plate and surmounted y a mushroom-head, a socket fitting said head, a mast supported by said casting, a boom pivotally secured to said mast, and a brace secured to said casting comprising a verticallydisposed plate, and a horizontally-extending flange curved along its inner edge to fit said conical standard.

3. In a hoisting-derrick, the combination with a base, a bearing secured thereon comprising a securing-plate, a conical standard,

and a mushroom-head, a socket-casting fit- In testimony whereof I affix my signature ting said bearing, a mast supported by said K in the presence of two Witnesses.

casting, a boom, a socket for said boom piv- JOHN BASS otally secured to said mast, and a reinforcing device comprising a plate bolted to said cast- Witnesses:

ing, and having an inwardly-projecting flange C. VELORTERMANN, engaging below said mushroom-head. l MAX H. SRoLovrrz. 

